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Search: id:A072350
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| A072350 |
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E.g.f. A(x) satisfies A(A(x)) = tan(x), where A(x) = Sum_{n>=1} a(n)*x^(2n-1)/(2n-1)!. |
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1
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| 1, 1, 3, 17, 225, 3613, -42997, 8725357, 2116966081, -549193907111, -114757574954509, 117893333517545097, 14433599120070484321, -65568697910890921624715, 2968238619232726100394235, 86999609037195113208781248165
(list; graph; listen)
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OFFSET
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1,3
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COMMENT
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The inverse of this g.f. A(x) is the g.f. of A095885. - Paul D. Hanna (pauldhanna(AT)juno.com), Dec 09 2004
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EXAMPLE
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a(x) = x/1!+x^3/3!+3*x^5/5!+17*x^7/7!+225*x^9/9!+3613*x^11/11!-42997*x^13/13!+...
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PROGRAM
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(PARI) {a(n)=local(A, B, F); F=tan(x+O(x^(2*n+1))); A=F; for(i=0, 2*n-1, B=serreverse(A); A=(A+subst(B, x, F))/2); if(n<1, 0, (2*n-1)!*polcoeff(A, 2*n-1, x))} (Hanna)
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CROSSREFS
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Cf. A048602, A048603, A052134, A052135.
Cf. A095885 (inverse).
Sequence in context: A133991 A009494 A075271 this_sequence A084040 A009495 A153487
Adjacent sequences: A072347 A072348 A072349 this_sequence A072351 A072352 A072353
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KEYWORD
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sign
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AUTHOR
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Vladeta Jovovic (vladeta(AT)eunet.rs), Jul 17 2002
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EXTENSIONS
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More terms from Paul D. Hanna (pauldhanna(AT)juno.com), Dec 09 2004
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